public void CreateDataIndexGetBytesLengthOf32()
{
var dataIndex = new DataIndex(1, 1, 1, 50);
var bytes = dataIndex.GetBytes();
int count = bytes.Length;
Assert.AreEqual(32, count);
}
public void CreateDataIndexGetBytesAndConvertBackToDataIndex()
{
// create the initial index and convert to bytes.
var dataIndex = new DataIndex(1, 1, 1, 50);
var bytes = dataIndex.GetBytes();
// convert the bytes back into a data index structure
var newDataIndex = DataIndex.Parse(bytes);
Assert.AreEqual(dataIndex.DocumentKey, newDataIndex.DocumentKey);
Assert.AreEqual(dataIndex.Pointer, newDataIndex.Pointer);
Assert.AreEqual(dataIndex.RecordLength, newDataIndex.RecordLength);
}
/// <summary>
/// Updates the data index located in the data index file.
/// </summary>
/// <param name="dataIndex">The changed data index to update.</param>
public void UpdateIndex(DataIndex dataIndex)
{
// add the index to the dataindex file.
_binaryWriter.BaseStream.Position = dataIndex.Position;
_binaryWriter.Write(dataIndex.GetBytes());
_binaryWriter.Flush();
_cache.Clear();
}
/// <summary>
/// Adds an index to the Data Index file.
/// Overwrites the first data index found with a 0 for its document key.
/// </summary>
public void AddIndexOverwriteDeleted(DataIndex dataIndex)
{
// add the index to the dataindex file.
_binaryReader.BaseStream.Position = 0;
while(_binaryReader.BaseStream.Position < this.FileSize){
// load the bytes, convert to index object and return
byte[] dataIndexBytes = _binaryReader.ReadBytes(32);
var existingDataIndex = DataIndex.Parse(dataIndexBytes);
// check if null
if (existingDataIndex.DocumentKey == 0){
_binaryWriter.BaseStream.Position = _binaryReader.BaseStream.Position;
_binaryWriter.Write(dataIndex.GetBytes());
_binaryWriter.Flush();
return;
}
}
// not found so add to end.
AddIndex(dataIndex);
}
/// <summary>
/// Adds the Data Index to the Data Index file.
/// WARNING: This function does not check for duplicates and can cause problems with duplicate Data Index's.
/// Only use AddIndex if you have some other method of making sure the Data Index's being stored are unique.
/// e.g Using an Auto incrementing Search Key (Primary Key). Using AddIndexCheckForDuplicate is slower but makes sure there is no duplicates.
/// Note: The Data Index is the pointer to the record in the entites data file.
/// </summary>
public void AddIndex(DataIndex dataIndex)
{
// add the index to the dataindex file.
_binaryWriter.BaseStream.Position = this.FileSize;
_binaryWriter.Write(dataIndex.GetBytes());
_binaryWriter.Flush();
// advance the file size on. its better that we do it than call the length all the time as its quicker.
this.FileSize += 32;
//_cache.Clear();
}